Hybrid Indoor Navigation as sistant for visually impaired people based on fusion of proximity method and pattern recognition algorithm

摘要

This paper presents an audio guided Indoor Navigation Systems built in a wearable device designed to work with a hybrid mapping. This mapping consist of radio frequency markers as well as visual markers located in special places inside known ambient. This system allows blind users a safe guided navigation with quick and low computational complexity. The chosen methodological approach divides the system in two stages: one offline and another online. In offline stage the indoor mapping is made through construction of markers to generate a contextual database that increases the quality of location indication. The online stage, where the indoor navigation is performed, is based on the proximity method, visual pattern recognition, odometry, and ultrasonic perception of barriers. Results showed rates of over 90.0% of the recognition of RF and visual markers with time of 0.4 seconds, as well as over 95.0% of positive ultrasonic perception of obstacles.